Thomas Jefferson Papers

To Thomas Jefferson from Francis DaCosta, 20 November 1804

Philadelphia The 20th. November 1804


The interest you have constantly manifested for all discoveries, connected more or less with the prosperity of the United States, will I hope make you forbear the liberty I have taken of Sending you the Sample of a lead mine discovered on my plantation and which I cause but lately to be opend. The vein has appear’d off the Surface of a Hill almost eighty feet above the highest rise of a creek at the bottom of it: at first the vein went down under an angle of about 40 degrees, but altered very Soon to a course almost perpendicular encreasing So much in about nine feet depth as to have enlarg’d from two to fifteen inches Solid ore duly walled in on each Side with the mineral Stones usually enclosing real veins of ore.

Having made a regular opening to ascertain the Course direction and thickess and broke down the mineral bank, about two tons of fine ore was collected in less than four hours, one ton more remaining at the bottom of the pit—The Samples I have The honor to Send you has been taken from a piece of pure galena weighing nine hundred weight at least. The strata of the Country is a Specie of red Slate in this the vein has been discovered. Other places on the plantation have evident Signs of the Same mineral So as to induce a belief that the vein I have been upon is a branch only of one more valuable and running to a Considerable extent. My farm lays at the mouth of perkiomen Creek, County of Montgomery State of Pensilvania, distant about twenty two miles from Philadelphia—The ground being much broken abounds with Springs which and the never-failing-water of the Creek will admit extensive water works to carry on the extracting of lead and its manufacturing in any nature or Shape whatsoever—

This Short account of this discovery I have thought was due to the Eminent Philosopher and naturalist I have The honor of addressing and Should it prove acceptable I request it may be Considered as a proof of the great respect with which

I am Sir—Your Most obedient & Humble Servant

Fcis DaCosta

DLC: Papers of Thomas Jefferson.

Index Entries